NEW ORLEANS (AP) — BP is making a case that it shouldn't pay the top penalty of $13.7 billion for polluting the Gulf of Mexico five years ago.

The oil giant struggled for 87 days to contain millions of gallons of spilling crude, its expert witness called the company's response exemplary.

Frank Paskewich is president of Clean Gulf Associates. He said BP recovered or dispersed 37 percent of the spilled oil, compared to just 8 percent in the Exxon Valdez disaster. Under questioning, Paskewich acknowledged that the long-term impact of the chemicals BP used to break down the oil is unclear.

BP PLC's market value is $122 billion, but it says paying the top fine would strain the finances of its exploration unit.

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